The present invention relates broadly to a methods for treating food products to increase their usable shelf life and, more particularly, to a method for treating nuts in a vacuum to remove substantially all the oxygen therefrom while leaving the nut meat in a flavorful, edible condition, and a nut thusly treated. The treated nuts may then be stored, roasted, baked, or otherwise processed for packaging and shipping.
Nuts, like other organic food matter, have a definite shelf life after which time the nuts may become spoiled beyond an edible condition. This problem is particularly acute with walnuts, pecans, and other relatively expensive nuts. For example, pecans have a shelf life of approximately six months which can be extended through the use of cold storage. Further, the nuts may be coated with honey, sugar, other flavoring, spice, or seasoning which can enhance the flavor yet increase the rate of spoilage.
U.S. Pat. No. 2,631,938 to Miers et al teaches coating peanuts with an anti-oxidant to reduce the spoilage. This technique extends the shelf life of nuts, yet spoilage eventually occurs.
U.S. Pat. No. 2,218,713 to Kelly et al teaches sealing peanuts in their shells while maintaining the in-shell environment at a reduced pressure to retard spoilage. This technique works reasonably well yet is confined to shelled nuts and does not provide for nuts sold outside of their shell such as walnuts or pecans.
As previously mentioned, it is known to coat nuts with flavoring. For example, U.S. Pat. No. 4,501,758 to Moore teaches soaking nuts in an aqueous solution to form an adhesive, then coating the nuts with a dry powder-like honey-containing mixture for flavoring.
While the above-discussed patents teach various ways of enhancing flavor and shelf life of certain types of edible nuts, it remains desirable to further increase the shelf life of unshelled nuts which may or may not be coated with flavoring.